The objective of the proposal is to noninvasively determine flow patterns and calculated blood velocities across the pulmonic valve. Special emphasis will be given in the quantification of the instantaneous blood velocity vector and the degree of disturbed flow at prescribed locations along the axis of the transvalvular flow stream which is perpendicular to the plane of the valve orifice. The centerline blood velocity along this axis will be applied to an appropriate hemodynamic flow model. From this model, transpulmonic pressure gradients and orifice areas will be calculated and compared to blood velocities, pressure gradients, and areas obtained invasively. Pulse Doppler echocardiography (PDE) is a new, noninvasive, ultrasonic technique used to evaluate blood flow characteristics at specific locations within the heart and great vessels. Limitations in the accuracy of the blood velocity measurements are a consequence of many factors. The two predominent problems are 1) determination of the Doppler angle, and 2) relative motion of the velocity field and the flow sensitive region, the sample volume (SV). In this study, the aforementioned problems will be minimized by innovative methodology which has been developed by this research team. Patient populations will undergo PDE examinations with the implementation of a newly developed sample volume tracker. Transvalvular flow parameters will be identified from the audio spectrograms, real-time spectral analyzers, and the calibrated flow velocities. Velocities and pressure gradients will be calculated and compared to invasive data. Normal and abnormal flow patterns will be identified and correlated to hemodynamically proven diseased valves. These established patterns will be used in a blind study of 25 patients who will undergo a standard echocardiograph examination and cardiac catheterization. It is hoped that the overall study will demonstrate the utility of the modified PDE technique in the diagnosis of pulmonic valve diseases and the determination of the degree of disease involvement.